package com.thinkersre.service;


import com.thinkersre.util.RedisKeyUtil;
import org.springframework.dao.DataAccessException;
import org.springframework.data.redis.core.RedisOperations;
import org.springframework.data.redis.core.RedisTemplate;

import org.springframework.data.redis.core.SessionCallback;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;

@Service
public class LikeService {
    @Resource
    private RedisTemplate redisTemplate;
    //点赞
    public void like(int userId, int entityType, int entityId, int entityUserId){

        redisTemplate.execute(new SessionCallback() {
            @Override
            public Object execute(RedisOperations operations) throws DataAccessException {
                String entityLikeKey = RedisKeyUtil.getEntityLikeKey(entityType, entityId);
                String userLikeKey = RedisKeyUtil.getUserLikeKey(entityUserId);
                boolean isMember = operations.opsForSet().isMember(entityLikeKey,userId);
                operations.multi();

                if(isMember){
            operations.opsForSet().remove(entityLikeKey,userId);
            operations.opsForValue().decrement(userLikeKey);
        }else{
            operations.opsForSet().add(entityLikeKey,userId);
            operations.opsForValue().increment(userLikeKey);
        }

                return operations.exec();
            }
        });


    }
    //查询某实体点赞数量
    public long findEntityLikeCount(int entityType, int entityId){
        String entityLikeKey = RedisKeyUtil.getEntityLikeKey(entityType, entityId);
        return redisTemplate.opsForSet().size(entityLikeKey);
    }
    //查询某人对某实体的点赞状态
    public int findEntityLikeStatus(int userId, int entityType, int entityId){
        String entityLikeKey = RedisKeyUtil.getEntityLikeKey(entityType, entityId);
        return redisTemplate.opsForSet().isMember(entityLikeKey,userId)?1:0;
    }

    //查询某个用户获得的赞
    public int findUserLikeCount(int userId){
        String userLikeKey = RedisKeyUtil.getUserLikeKey(userId);
        Integer count = (Integer)redisTemplate.opsForValue().get(userLikeKey);
        return count==null ? 0 : count.intValue();
    }

}
